The fire broke out on Bayview Avenue, where houses are closely packed, just after 4 a.m.
The flames then jumped to the second home before firefighters were able to prevent further spreading.
Ten residents in the two houses were forced out.
A neighboring apartment building was also evacuated as a precaution.
Two firefighters sustained minor injuries battling the blaze. One had a head injury, while the other suffered a groin injury.
Local streets were closed around the fire scene. The cause is under investigation.
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